The Slender-Billed Curlew Quest
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Species spotlight The Slender-billed (possibly extinct) by BirdLife – with no Curlew quest verified sightings since the early 1980s. We hope it can be proven that Slender- billed Curlew still exists.The most urgent On the very brink of extinction, the once numerous priority is to thoroughly search sites Slender-billed Curlew is a true enigma. Tim Cleeves, where the species is known to have wintered previously, as well as potential Nicola Crockford and Peter Köhler report on a last- moulting sites, although no moult site has ditch attempt to find the bird – and how you can help. yet been identified. It is likely to be easier to search the lender-billed Curlew is the Gretton et al 2002).The last flocks of more relatively few discrete, identifiable rarest bird in the Western than 100 were seen in Morocco at Lagune candidate sites in the putative wintering Palearctic. It is one of the five de Puerto Cansado, Khnifiss, in January and moulting range than the vast Sbird species in Europe – and 1964 (500-800 birds) and at Oued continuous area of potential breeding 190 in the world – most threatened with Chebeika in December 1974 (123 birds). habitat.Thus, unless stable isotope research global extinction, and classified as However, Slender-billed Curlew is narrows the search to within a radius of Critically Endangered by BirdLife easily overlooked and challenging to about 100-200 km, it is less of a priority International and the IUCN. identify, and could be present in countries to continue the ‘needle in the haystack’ There have been no verified records such as Iraq and Iran, which have been search for Slender-billed Curlew in its anywhere since 1999, when birds were relatively inaccessible to skilled birders in probable breeding range in Russia and seen in Greece in April and Oman in recent years. Kazakhstan. February and August.This last sighting There is a higher chance of catching involved three juveniles, indicating that Last chance birds at wintering sites, where they stay breeding must have occurred that year.At This article is intended to help launch a for prolonged periods, rather than passage the last-known regular wintering site, ‘final push’ to find this enigmatic species sites that they may go through quickly. Merja Zerga in Morocco, there have been before it is too late. If we lose Slender- This makes satellite tagging easier, which no verified records since 1995. billed Curlew, it will be the first is vital to find the breeding, passage, The only verified records of nesting extinction of a European bird since Great moult and wintering sites in order to take Slender-billed Curlews all date from the Auk in June 1844 and Canary Islands conservation action for the species. first quarter of the 20th century and Oystercatcher in 1981 (BirdLife We hope this article will inspire readers occurred near Tara, east of the Urals in the International 2008a). Eskimo Curlew, the to plan their birding holidays and organise Omsk region of south-west Siberia birds’ close relative in the Nearctic, is expeditions to the most likely Slender- ៑ CHRIS GOMERSALL (WWW.RSPB-IMAGES.COM) (Ushakov 1909, 1912, 1916 and 1925; already classified as Critically Endangered billed Curlew sites. In addition, the special This adult Slender-billed Curlew, one of several that used to winter at Merja Zerga, Morocco, in the early 1990s, was last seen in February 1995. There have since been no verified records at the site. REPRODUCED FROM The home of birding www.birdwatch.co.uk WWW.BIRDWATCH.CO.UK JANUARY 2009 • BIRDWATCH 43 Species spotlight laminated ‘toolkit’ enclosed exclusively Past records autumn. Almost a third are from another with this month’s Birdwatch has been eight countries: Ukraine – 33 in all seasons, designed to be taken into the field, and The Slender-billed Curlew Working Group but more in autumn; Serbia – 30 in autumn (SBCWG) collects and documents all and spring, but also in summer; Tunisia – includes an identification guide and advice records of the species on a database; visit 29 mainly winter; Turkey – 24, in all on steps to take if you are lucky enough to www.slenderbilledcurlew.net. It separates seasons but more in summer; Bulgaria – find a potential Slender-billed Curlew. those listed before and after 1990. It also 23 in spring, autumn and winter; Iran – 19, distinguishes three categories of records: mainly in winter; Romania – 18 in all Breeding ecology ● Verified records: these are authenticated seasons, but mainly autumn; and Russia – Like Eskimo Curlew in North America, in by national organisations – rarities 17, mainly in spring but some also in committees, BirdLife partners and so on – summer and autumn. the 19th century Slender-billed Curlew or, in the absence of such bodies, by other About 85 per cent of the verified records was regarded as common in Europe in experts. They include records regarded as since 1900 are from these 12 main range countries such as Romania, Hungary, Italy ‘confirmed’ by Gretton (1991 and 1994) states, all of which have had at least 10 and Greece. It outnumbered the two other unless proved otherwise by the relevant verified records during that period. There European curlew species – Eurasian Curlew national organisations or by the original are another 12 range states with between and Whimbrel – in several areas, including observer. three and nine verified records since 1990: ● Unverified records: these are mainly summer – Kazakhstan; mainly Sicily, Malta,Tunisia, Morocco and Algeria, unsubstantiated by any details such as a autumn – Poland, Austria, Malta, Iraq and and sometimes occurred in spectacular, description or photograph, or are those on Yemen; mainly winter – Algeria, Egypt, Iraq, thousands-strong flocks. Even then, before which a national organisation has not yet Oman, France and The Netherlands; mainly its dramatic decline, which was probably reached a decision or suggests that there spring – Bosnia-Herzegovina and Cyprus. due to overhunting and exacerbated by is doubt, but are not yet rejected. This Only about 20 per cent (128) of the habitat loss, very little was known about includes those treated by Gretton (1991 verified records since 1900 have been of and 1994) as unconfirmed, unless proven more than three birds, with just over half the bird’s ecology. otherwise. referring to single birds. According to Ushakov’s 1925 paper, ● Rejected records: these have been Slender-billed Curlews have often been confirmed nest sites near Tara, including a rejected by a national organisation or other seen in close association with Eurasian colony of 14 nests, were in an extensive relevant experts. Curlews. Associations with other waders quaking peat bog with dense cover of More than half of the 617 verified such as Whimbrel, Black-tailed Godwit, sedge mixed with Mares’Tail Equisetum, records for 1900 to 1999 come from four Grey Plover, Northern Lapwing and Tringa countries: Italy – 99 verified records, mostly species are not usually close (Gretton 1991). with willow, birch and pine present.The spring but some also in autumn and winter; It should be borne in mind that the birds arrived in the area from 10 May. Greece – 85, all seasons but mainly in number and distribution of records are With such a small sample and an spring; Morocco – 76, mainly in winter; and heavily influenced by the number and account dating back more than 80 years, Hungary – 66, all seasons but mainly in distribution of skilled birdwatchers. when the species was already in decline, it would be wrong to conclude that all Slender-billed Curlews bred or breed in taiga marsh, or that the breeding dates remain the same now as they did in Ushakov’s day.The bog-forest transitional habitat he described during the early 20th century appeared similar in 1990 but by 1997 was already destroyed, having become afforested, and with adjacent areas cultivated (Gretton et al 2002). ADAM GRETTONADAM All verified records of Slender-billed Curlew since 1900. Summer: June-July (45 records); autumn: August-November (196); winter: December-February (167); Autumn Summer spring: March-May (185). Spring Winter COURTESY OF RSPB The only known breeding site for Slender-billed Curlew was in the forest- steppe zone in the vicinity of Omsk and Novosibirisk. 44 BIRDWATCH • JANUARY 2009 WWW.BIRDWATCH.CO.UK Species spotlight Danilenko et al (1996) analysed Britain’s sole record vegetation maps in these areas and in of Slender-billed other locations where birds had been Curlew (left, with recorded during summer in the 1800s. Eurasian Curlew), They summarised the breeding habitat at Druridge Bay, requirements as forest-steppe: “Open, Northumberland, locally wet areas with dense sedge or dates back to early May 1998. grass vegetation, with patches of bare JIM PATTINSON ground, relief which is not flat (moderate elevations and depressions), and with complete by October-December, which 1997), Kazakhstan (July-September adjacent shrubs or woodland patches excludes flight feathers, upperwing 1998), Russia (Tumen plains and Omsk formed by deciduous trees and/or pines.” coverts, tail, some scapulars and most region, 1999), Iran (January-February Such habitat within western Siberia tertials. In spring, most feather tracts are 2000), Morocco (Lagune de Khnifiss, extends in area to between 200,000 and renewed again, but flight feathers remain December 2001),Yemen (November 400,000 sq km. unmoulted. 2001-January 2002), Iran (January Indeed, Ushakov’s observations were 2002),Tunisia (January 2003), Libya made towards the northern edge of the Habitat preferences (January 2005), Ukraine (July-August forest-steppe zone, with parts of the At wintering and migration stop-over sites 2006) and Uzbekistan (April-May 2007 marsh having some characteristics of the the species appears to be something of a and April-May 2008). taiga, such as the presence of conifers.